I'm going to jump in here and announce that William Furneis (1579 Paignton) and his wife Joane Chadder are also my great x10 grandparents! My most recent Furneaux ancestor is Caroline Furneaux (great x3 grandmother) daughter of Christopher Furneaux and Mary Clement, bapt. 1820 in Buckfastleigh, married William Waycott 1843 and died 1863.
I haven't looked at that branch of my tree for a while, but much of my information came from an extensive tree, possibly on the old Rootsweb.
www.furneaux-family.com no longer exists, though it may survive on the Wayback Machine. That gave William's parents as Henry Furneys, buried in Paignton 25 July 1626 and his wife Cicely, buried in Paignton 25 Jul 1614. The burial records are on FindMyPast, and Cicely is described as w(ife) of Henry Ffurneis Sen. I haven't yet found a marriage for Henry and Cicely, but I've got lots of free time now to hunt for it. Looking forward to more correspondence on this family, there must be a lot of descendants around!